Magnetic switch assembly for operation by magnetic cards



W. W. BARNEY MAGNETIC SWITCH ASSEMBLY FOR OPERATION BY MAGNETIC CARDSOriginal Filed June 50, 1967 Q Q) Q Q Q 94 (3 (c) Q @fl B), ve/fg4zA iyUnited States Patent 3,474,366 MAGNETIC SWITCH ASSEMBLY FOR OPERATION BYMAGNETIC CARDS Walter W. Barney, 4837 Woodley Ave., Encino, Calif. 91316Original application June 30, 1967, Ser. No. 650,483, now Patent No.3,430,200, dated Feb. 25, 1969. Divided and this application July 5,1968, Ser. No. 742,809

Int. Cl. H01h 9/54 US. Cl. 335-206 4 Claims ABSTRACT OF THE DISCLOSURE Aplate supports a plurality of evacuated bulbs in respective openings.Each bulb houses a switch comprising a slidable magnet adjacent one faceof the plate, and fixed contacts connected to leads at the oppositeface. The magnets in one form are plated to act as movable contacts, andin another form support contacts for movement therewith. When a card isplaced adjacent said one face with embedded magnets aligned with themovable magnets, only the movable magnets of opposite polarities arecaused to close their associated fixed contacts.

CROSS-REFERENCE TO RELATED APPLICATION This application is a division ofmy application, Magnetic Card and Validator Apparatus, Serial No.650,483, filed June 30, 1967, now Patent No. 3,430,200.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to so-called magnetic card readers, and more particularly to animproved magnet operable switch and reader plate assembly employing aplurality of such swtiches.

Description of the prior art In devices heretofore known which employswitchces operable from magnets embedded in a card, the card magnets areflat strips with their poles on lines parallel to the card faces. Themovable magnets are supported with their poles in planes parallel to thecard magnets, and are adapted for sliding or pivotal movement in suchplanes to close respective pairs of switch contacts. The direction ofmovement of such a magnet depends upon whether a card magnet adjacentthereto is in polarity opposing or attracting relation thereto.

A disadvantage in such arrangements is that a significant portion of theavailable magnetic fields linking aligned card and movable magnets isneeded to overcome magnetic force components tending to subject themovable magnets to transverse movement. In this connection, it will beseen that when relatively fixed and movable parallel magnets are broughtclose together, the movable magnet tends to be drawn toward or movedapart from the fixed magnet, depending upon whether their correspondingends are of like or opposite poles.

Still further, magnets mounted for pivotal movement have inherentbearing friction. A substantial portion of available magnetic fieldslinking aligned card and pivotal magnets necessarily is used to overcomesuch friction.

For such reasons, movable magnets frequently fail to operate properly,thereby preventing the establishment of signal information for authenticmagnetic cards. Such prior art arrangements are thus not suitable formagnetic credit and security card systems which require a high degree ofrepeatability and reliability in operation of magnet switches inresponse to properly coded magnetic cards.

Summary of the invention My invention embraces a magnetic switch whereinan evacuated envelope houses a pair of fixed contacts, and a slidableaxially poled magnet and contact combination for making and breakingcontact between the fixed contacts. Further, my invention embraces anassembly of a plate supporting a plurality of such switches with theirmagnets movable along parallel axes toward and away from one face of theplate, and also a combination therewith of a card having axially poledmagnets to be aligned with such movable magnets.

I thus eliminate the prior art problems involving the loss of asignificant portion of fields of aligned card and movable magnets neededfor the task of overcoming magnetic and mechanical friction forces thatresist the desired movement of switch magnets. Further, my assembly isone in which I eliminate the likelihood of exposure of contacts to andthe contamination of contacts by dirt, moisture and the like.

Brief description of the drawing FIGURE 1 is a perspective view of aplate for slidably supporting magnet operable switches, in accordancewith my invention;

FIGURE 2 is an enlarged longitudinal sectional view of a switch of myinvention wherein an evacuated bulb supports a conductive magnet formovement into and out of engagement with fixed contacts;

FIGURE 3 is a top plan view of the plate of FIGURE 1 with magnetssupported therein, illustrating a pattern of orientation of the magnets;

FIGURE 4 is a fragmentary sectional view of the plate of FIGURE 3showing the magnets of FIGURE 3 in place and a credit card disposedadjacent to the plate; and

FIGURE 5 is a lonigtudinal sectional view of a modification of my switchwherein the evacuated bulb houses a conventional magnet on which aconductive contact is adapted to move into and out of engagement withfixed contacts.

Description of the preferred embodiments Referring to FIGURES 1-4, acard 88 with embedded, axially poled magnets is adapted to be placedadjacent one face of a plate 90 that has openings 92 arranged in fourrows 94, 96, 98, of ten openings each. Fastened in each of the openings92 is an evacuated bulb 102 which houses of movable permanent magnet 104adjacent one end, and a pair of opposed, fixed contacts 106, 108 whichextend through the other end. As shown, leads 110, 112 are connected tothe external end of the contacts 106, 108. Near the end adjacent themagnet 104, the bulb is encircled by a soft iron ring 114. As shown, theinner end of the magnet 104, which may be pointed, is adapted to engagethe confronting ends of the fixed contacts 106, 108. The magnets 104 aremade conductive, as by being plated with conductive metal, so that theengagement of such a magnet with its associated fixed contacts 106, 108establishes a direct connection between such contacts.

FIGURE 8 illustrates a plan view of the face of the plate 90 to whichthe flat ends of the magnets 104 extend. In FIGURE 3, these ends of themagnets are shown with the polarities distributed in accordance with amaster pattern. In the particular pattern here illustrated, the magnets104 are so poled that the outer ends of the middle two magnets in row 94are of the same polarity (south), and the polarities of the magnetsextending toward the outer ends of that row are alternating north andsouth poles. The same arrangement is followed in row 98. Rows 96 and 100are similarly arranged, but with the polarities of the magnets beingopposite to those of the corresponding ones in the rows 94 and 98.

When the card 88 is placed with its magnets 80 aligned with respectivemovable magnets 104, those magnets 104 which are in polarity attractingrelation to the associated card are attracted, and those in polarityopposing relation are repelled. As illustrated at the bottom or" FIGURE4, each of the reversed polarity card magnets 80 repels the associatedmovable magnet 104 and causes it to establish a conductive connectionbetween the associated fixed contacts 106, 108.

In this latter connection, it is assumed the card is coded, in that thepolarities of the faces of the card magnets adjacent the plate 90 are,except for a predetermined number (e.g., four) of them, opposite to thepolarities of the ends of the movable magnets with which they arealigned. Thus, with the four magnet switches operated from the fourmagnets 80 which form the card code are adapted, through theirassociated leads 110, 112, for connection to a network to providedesired signal information identifiable with the card.

When the card 88 is removed from alongside the plate 90, the magnets 104which had moved into conductive contact with fixed contacts 106, 108 areautomatically disengaged from such fixed contacts and returned to thenormal position shown in FIGURE 2. This is accomplished by the adjacentsoft iron ring 114. With the force of repulsion removed by withdrawingthe card from the slot, all of the magnets 104 are urged, via magneticattraction to the soft iron rings 114, to the adjacent ends of theirbulbs 102.

The bulb 102 may be made of glass or plastic. Also, the magnet 104 maybe made nonconductive, but adapted to carry a conductive contactelement. For example, and referring to FIGURE 4, there is shown a magnet120 which has one end of a contact 122 secured to its inner end, e.g.,as by suitable cement indicated at 124. The other end of the contact 122is shaped to enter between and make contact with the inner ends of thecontacts 106, 108.

While the magnetically controlled switches above described are arrangedto function as normally open switches, it will be apparent that myinvention embraces the alternative arrangement, in which the variousswitches are normally closed. In such case, the coded magnets in thecard attract the corresponding movable magnets, thereby to open thoseswitches. All the remaining switches remain closed as a result ofrepulsion by the magnets in the card. Still further, my invention willbe seen to embrace the arrangements of switches wherein normally openswitches are closed or normally closed switches are opened, by eitherrepulsion or attraction.

Again referring to FIGURE 4, the leads 110, 112 extend through the endsof the openings 92 opposite the face of the plate 90 against which thecard 88 is to be located. The leads 110, 112 are shown extending throughopenings in ablock 128 of insulation material, e.g., plastic, which issuitably secured, as by adhesive, to the adjacent surface of the plate90. As shown, one of the leads 112 of each pair is connected to a pointof reference or ground potential. The remaining leads are available forconnection to a network as previously mentioned. From the foregoing, itwill be apparent that various modifications can be made in thestructures shown and described Without departing from the spirit andscope of my invention. Accordingly, I do not intend that my invention belimited, except in accordance with a reasonable interpretation of theappended claims.

I claim: 1. In combination: an evacuated housing; a pair of fixedcontacts extending into said housing; an axially poled magnet in saidhousing, said magnet carrying a contact element, each magnet beingmovable axially in one direction to bring said contact element intoengagement with both fixed contacts, and movable axially in the oppositedirection to break contact between said contact element and said fixedcontacts; and magnet bias means adjacent one end of said housing forbiasing said magnet to a predetermined normal position with respect tosaid fixed contacts. 2. The combination of claim 1, wherein said biasmeans includes a ring of magnetic material surrounding said housing andnormally attracting said magnet to a position wherein said contactelement does not engage said fixed contacts.

3. The combination of claim 2, including a plate having a plurality ofopenings therethrough; a plurality of said housings, each located in arespective one of said openings; a nonconductive sheet overlaying theface of said plate adjacent said fixed contacts; and respective leadsfrom said fixed contacts extending through said sheet. 4. Thecombination of claim 3, including a card having a plurality of magnetsembedded therein and adapted to be positioned adjacent the opposite faceof said plate with the magnets in said card aligned with respectivemagnets in said housing,

a plurality of magnets in said card being poled to attract theassociated movable magnets toward said opposite face, the remainingmagnets in said card being poled to repel the associated movable magnetstoward said fixed contacts.

References Cited UNITED STATES PATENTS 3,154,761 10/1964 OGorman 335-207X 3,281,735 10/1966 Blumish 335207 3,376,527 4/1968 Risk 335207 BERNARDA. GILHEANY, Primary Examiner R. N. ENVALL, JR., Assistant Examiner

